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Virulent Newcastle 

Disease Virus Response

Surveillance Sampling Commercial

Premises in Surveillance Zone and 

Free Area

Please note: These procedures may be revised as the situation develops. June 5, 2018

 

DEFINITIONS

Infected Zone: Zone that immediately surrounds an Infected Premises.

Buffer Zone: Zone that immediately surrounds an Infected Zone or a Contact Premises.

Control Area: Consists of an Infected Zone and a Buffer Zone.

Surveillance Zone: Zone outside and along the border of a Control Area. The Surveillance Zone is 

part of the Free Area. 

Foreign Animal Disease Investigation: An investigation conducted according to VS Guidance 

Document 12001 (Ready Reference Guide for investigations is here).

INTRODUCTION

An Infected Zone and Buffer Zone (Control Area) will be created around an Infected Premises. This 

document provides surveillance guidance for commercial poultry1premises outside a Control Area

in the Surveillance Zone. Surveillance activities and associated testing should be based on 

recommendations of the Unified (State-Federal) Incident Command; this guidance may require 

further modification based on epidemiological and situational information.

Newcastle disease, caused by vNDV, is endemic in a number of countries in Asia, the Middle East, 

Africa, and the Americas. Newcastle disease was detected in backyard poultry in California in 2018. 

Previous Newcastle disease outbreaks in poultry in the United States occurred in the States of 

California (2002–2003), Nevada (2003), Arizona (2003), and Texas (2003). Virulent NDV is 

endemic in wild cormorants and non-virulent forms of ND are endemic in poultry. There are nonvirulent strains of NDV endemic in poultry. This document reflects the epidemiological information 

known about the behavior of vNDV from knowledge gained in the 2003–2004 U.S. outbreak. 

COMMUNICATION

It is critical to ensure that disease information, as well as recommended biosecurity measures, is 

clearly communicated to all commercial premises in a Surveillance Zone. APHIS and State/Tribal 

 

1 For this document, poultry is defined as any domesticated bird raised for food or fiber; this excludes the poultry displayed in 

a licensed exhibition or zoo. 
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officials must ensure that instructions are provided to owners/producers to report clinical signs and 

abnormal mortality. Transparent procedures should be used to manage reports of clinical signs or 

unusualmortality from commercial producers (also known as sick bird calls).

VISITING PREMISES

While it is important to locate commercial poultry premises within a Surveillance Zone, responders 

should not enter premises unless instructed to do so by the Incident Management Team (IMT). It is 

critical to remember that any real or perceived belief that responders are spreading disease is 

incredibly detrimental to the response effort. As with any premises, if a visit is necessary, 

responders should observe appropriate biosecurity and cleaning and disinfection measures and 

follow all guidance provided by Incident Command.

SURVEILLANCE PLAN

Passive Surveillance

Passive surveillance is conducted at all times in the United States through foreign animal disease 

investigations (per VS Guidance Document 12001). In the event of a foreign animal disease 

detection, passive surveillance should be intensified through rapid and clear communication to all 

producers in the Surveillance Zone, following IMT procedures.

Mortality threshold levels that signal the need for investigation have been established for the different 

commercial poultry sectors. Commercial flocks that exceed the mortality thresholds listed below are 

investigated and sampled as rapidly as possible for virulent ND.

 Commercial broilers: mortality exceeding 3.5 birds/1,000 per day.

 Commercial layers: mortality exceeding 3 times the normal daily mortality (normal:

0.13 birds/1,000 per day for layers from 2 to 50 weeks, and 0.43 birds/1,000 per day for 

layers over 50 weeks); OR 5 percent drop in egg production for 3 consecutive days.

 Commercial turkeys: mortality exceeding 2 birds/1,000 per day.

 Broiler breeders: mortality exceeding 2 birds/1,000 per day.

 Layer breeders: mortality exceeding 3 times the normal daily mortality (normal: 0.2 

birds/1,000 per day up to 50 weeks, and 0.37 birds/1,000 per day after 50 weeks).

 Turkey breeders: mortality exceeding 2 birds/1,000 per day; OR a decrease in egg 

production of 15 percent occurring over a 2-day period.

 Small-volume high-value commercial poultry flocks and other commercial flocks not listed 

here: any sudden and significant mortality event or sudden drop in egg production should be 

investigated.

At the State’s discretion, investigation and sampling of flocks that exceed the mortality thresholds can 

be performed by a company veterinarian, a Foreign Animal Disease Diagnostician, or other IMTdesignated response personnel. Schedule an appointment to collect samples as quickly as possible

and conduct sampling according to the recommended sampling scheme below. Submit samples to the 

designated National Animal Health Laboratory Network (NAHLN) lab as indicated by the IMT.

Active Surveillance

In addition to passive surveillance, active surveillance is conducted to find cases and provide evidence 

that the pathogen is not present. Active surveillance in commercial premises during an outbreak is 
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composed of two components: response surveillance and surveillance for permitted movements of 

poultry and poultry products, referred to as pre-movement surveillance. This document describes 

response surveillance activities only. 

These strategies regarding sampling sizes and sampling frequencies pertain to commercial premises 

located in the Surveillance Zone. 

RECOMMENDED SAMPLING SCHEME

Premises Level

1. Select the appropriate number of premises to sample following guidance in Table 1 below.

Prioritize commercial premises that are closest to the presumptive or confirmed vND 

premises. Sampling the indicated number of premises will result in 0.95 probability that at 

least one positive premises will be detected if the prevalence of vNDV among additional 

premises in the Surveillance Zone is 1 percent or greater.

2. Collect samples from each barn every 5-7 days for 28 days, or use similar sampling frequency

depending on the resources available and guidance provided by the IMT.

3. Continue sampling commercial premises every 28 days for 3 months after the last detected 

vND premises2.

Bird Level

Select birds to sample as follows for detection of vNDV at a 10 percent prevalence with 0.95 

probability of detection, and collect samples in line with the current version of Recommendations for 

Collecting Specimens from Poultry for Viral Diagnostic Testing (WI-AV-0020 available here). 

Prioritize sampling of sick and dead birds; conduct pooling per WI-AV-0020. Random sampling of 

apparently healthy birds provides minimal detection benefit unless you are targeting poultry with a 

high risk of exposure to vNDV. Oropharyngeal or tracheal swabs are preferred for gallinaceous 

birds3 and cloacal swabs for domestic waterfowl. Do not combine swabs from different species or 

different sampling routes.

1. Sample at least 30 sick and dead birds per barn using 5- or 11-swab pools.

a. If there are more than 30 sick and dead birds, sample an additional 5- or 11- swab 

pool for each 50 sick and dead birds observed. 

b. If there are less than 30 sick and dead birds, sample the apparently healthy birds

near doorways, vents, and any area with a high potential for exposure to vNDV to 

obtain a total sample size of 30 birds.

2. Prepare, package, and process swabs for laboratory submission according to the guidance 

found in the Veterinary Services Guidance Document 12001, which provides guidance for 

the investigation of potential foreign animal disease/emerging disease incidents. VS 

Guidance Document 12001 is available here. 

 

2 OIE 2017 Terrestrial Animal Health Code Chapter 10.9 Infection with Newcastle disease virus.

3 Gallinaceous birds include chickens, turkeys, pheasants, partridges, grouse, quail, guinea fowl, and peafowl. 
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Table 1. Number of premises to be sampled in the Surveillance Zone if the total number of premises in 

the Surveillance Zone cannot be visited.*

No. of Premises Minimum No. of Premises

to be Sampled for 1% prevalence

Minimum No. of Premises

to be Sampled for 3% prevalence

less than 40 Sample all 39

80 Sample all 60

100 Sample all 66

150 136 76

200 163 82

400 221 92

600 247 96

1,000 271 99

1,500 285 100

2,000 292 101

3,000 299 102

5,000 305 103

10,000 309 103

infinite 314 104

1 Sample sizes computed using Cannon, 2001.

* Assuming a 95% herd-level sensitivity, sampling the indicated number of premises will result in 0.95 probability that at least 

one positive premises will be detected if the prevalence of virulent Newcastle disease virus is at least 1% or 3% in the 

population of premises at the time of sample collection.

DOCUMENTATION

As with all surveillance activities, documentation is critically important. EMRS2 is the system of 

record for all virulent ND outbreaks in the United States. Relevant data regarding surveillance 

activities must be entered into EMRS2 in as close to real time as possible. This data may be 

reported internally and externally through situation or close-out reports or other means.

At a minimum, the following items are important to maintain and report:

 Number of commercial premises in Surveillance Zone

 Number premises visited and sampled (including dates) for active surveillance

 Total birds sampled at each premises and visit

 Laboratory results for all submissions

FOR MORE INFORMATION

USDA APHIS VS. Draft August 2014. Newcastle Disease Response Plan: The Red Book. 

Recommendations for Collecting Specimens from Poultry for Viral Diagnostic Testing (NVSL WI-AV0020) 

USDA APHIS VS. 2018. FAD Prep Materials and References. www.aphis.usda.gov/fadprep.